Linux 6.6 Unconditionally Enables x86 CPU Microcode Loading Support

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PublicLewdness
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Joined: 03/15/2020

I came across this article on Phoronix today. It states

"Among the many changes to land during this first week of the Linux 6.6 cycle were the x86 CPU microcode loader updates that now unconditionally makes that support part of the x86/x86_64 kernel builds.

Intel engineers have been working on improvements to the Linux CPU microcode updating code. There's also been fundamental fixes to the x86 32-bit CPU microcode handling posted in recent weeks too.

For Linux 6.6 is an initial clean-up of the x86 CPU microcode loader and also making the loader core code unconditionally enabled and no longer under a Kconfig build-time switch to easily toggle its presence.

Intel and AMD CPU

Most everyone builds their kernels with x86 microcode updating support and it's certainly recommended these days where microcode updates commonly correct functional issues as well as taking care of CPU security vulnerabilities. Though having this support unconditionally enabled may be frowned upon by the likes of the GNU Linux-libre folks who are against run-time updating/handling of any microcode/firmware blobs.

"The first, cleanup part of the microcode loader reorg tglx has been working on. This part makes the loader core code as it is practically enabled on pretty much every baremetal machine so there's no need to have the Kconfig items. In addition, there are cleanups which prepare for future feature enablement."

The x86-microcode pull also has clean-ups in preparing for future feature enablement work in this microcode area."

Can anyone translate this for someone who isn't a coder ?

PublicLewdness
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Joined: 03/15/2020

forgot to add a link to the article:

https://www.phoronix.com/news/Linux-6.6-x86-microcode

jxself
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Joined: 09/13/2010

"Can anyone translate this for someone who isn't a coder?"

It means that issues pertaining to freedom with Linux will persist but with Linux-libre these concerns won't be present. And so, nothing very much will change.

PublicLewdness
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"It means that issues pertaining to freedom with Linux will persist but with Linux-libre these concerns won't be present. And so, nothing very much will change."

I could gather that much myself but was wondering specifically how the Linux kernel was getting worse.

jxself
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Joined: 09/13/2010

"specifically how the Linux kernel was getting worse."

By removing the Kconfig option. Imagine if you had a room and someone deletes the light switch and as a result the light is to be permanently "on", whether you want it or not. I'm not sure if this is the best analogy though because light bulbs are generally not harmful to you when they're on while proprietary software is harmful to your freedom.

Imagine a container with Plutonium (i.e. proprietary software) which is normally closed for your protection from the dangerous alpha particles (aka particles that cancel out your freedom) being emitted. Then, in a recent change, the box has been redesigned so that it's always open by not having a lid anymore. Even though, for your safety, the container should always be closed. As a result you hear your geiger counter ticking more frequently now. Perhaps it's time to call in Freedo:
https://jxself.org/git/?p=freedo.git;a=blob;f=Freedo+In+A+Hazmat+Suit.svg;h=6554c0351173d270d5728fe520986eb5fd2d96cf;hb=HEAD

PublicLewdness
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Joined: 03/15/2020

"By removing the Kconfig option. Imagine if you had a room and someone deletes the light switch and as a result the light is to be permanently "on", whether you want it or not. I'm not sure if this is the best analogy though because light bulbs are generally not harmful to you when they're on while proprietary software is harmful to your freedom.

Imagine a container with Plutonium (i.e. proprietary software) which is normally closed for your protection from the dangerous alpha particles (aka particles that cancel out your freedom) being emitted. Then, in a recent change, the box has been redesigned so that it's always open by not having a lid anymore. Even though, for your safety, the container should always be closed. As a result you hear your geiger counter ticking more frequently now. Perhaps it's time to call in Freedo:
https://jxself.org/git/?p=freedo.git;a=blob;f=Freedo+In+A+Hazmat+Suit.svg;h=6554c0351173d270d5728fe520986eb5fd2d96cf;hb=HEAD"

Thank you, that analogy works for me.